The Pittsburgh Post-Gazette reports that the Pennsylvania Public Utility Commission’s Bureau of Investigation and Enforcement is pursing cease-and-desist orders against San Francisco-based ride-share companies Lyft and Uber.

The companies have five days to respond.

Uber, Lyft and other ride-share companies use smartphone apps to dispatch drivers who use personal vehicles. The PUC contends they are operating illegally as transportation brokers and that the drivers are not licensed as motor carriers.

Last week, the PUC proposed daily fines of $1,000 per day for each company, and proposes fines of $1,000 for 23 drivers it cited in March and April.

Company representatives did not return messages left by the newspaper.